Manufacture of miniature incandescent lamps



INVENTOR REGIN LD K. BEAUMSDOKFF ATTO y 25, 1944- R. K. BRAUNSDORFF' MANUFACTURE OF MINIATURE INCANDESCENT LAMP Filed May 31, 1941 Patented July 25,-1-944 v V I 7 y UNITEDSTATES PATE T 'ZOFFICE 1 2,354,194 r MANUFACTURE OF lVflNIATURE INQANDESCENT LAMPS Reginald K Braunsdorfl, East Orange, N. 1., as-

signor to Tnng- Sol lamp Works, 1110., Newark, N. 1;. a corporation of Delaware Application May 31, 1941, Serial No. 396,013

3 Claims. (Cl. 176-36),

This invention relates to the manufacture of conventional small filament 2 and the convenminiature lamps and particularly miniature lamps tional slender leads 3, the latter being, for excf the very small variety such for example, as ample, of approximately .01 diameter, the drawlamps for recordingphonographs, Ipanel boards, ing illustrating these leads on an exaggerated flash lights, and the like. scale. The leads 3 are spaced from each other Miniature lamps ofthis character embody a and held in spaced relation by a conventional pair of slender support and lead wires which are mount bead 4 as, for example, of glass or other fused to and heldinspaced relation from each refractory fusible material, and in the convenother by a refractoryor glass bead, with the fila-' tional lamp bulb the lower parts 3 of the leads ment mounted on the free ends'of the lead wires 3 form the sole support for the bead 4 and the and with the ends ,or these slender lead wires filament 2'; these leads 3' being sealed between which are disposed on the opposite side of the the toptube 5 and the neck i' of the bulb accordbead from the filament being sealed between the 7 ing to the conventional manufacture of standard toptube and the bulb when'the'two are sealed tipless mounts. The bulb of my invention emtogether and forming the sole support for the bodies, in addition to these conventional parts, stem. It has been foundfthat in lamps of this a supporting wire 6 which is anchored to the character vibrations are transmitted to' the bead 4 at one end and is bent downwardly with mount through the long slender lead and supits end 6' sealed into the top tube and the neck port wires which form a two-point support. of the bulb when the top tube and the bulb neck These vibrations not only shorten the life 01 the are fused together. The stem is thereby suplamp but also render the lamp extremely inefliported and held against vibration by the leads clent for certain uses. For example, when vibra- 3, 3' and by the anchor or guide wire 6, thus retions of the mount occur in miniature lamps used sulting in a tripod support by the fusion of the for recording phonographs, distortion occurs in leads and the support wire 6 at the points I, I the reproduction with consequent loss of time and B into the seal formed between the top e and expense, and such vibrations occur irrespec- 5 andthe neck i of the bulb. The leg 0 of the tive of the age of the lamp. The standard'miniatripod support may be of the same metal as the ture lamp has a resonance point of vibration beleads 3; as f example the n n i Dumet tween 200 and 4000 cycles per second, depending leads, and may be of the same small diameter as upon the exact lamp construction. This resonant 0 the leads 3, or it may be even smaller in diamvibration when the lampis used in recording eter. phonographs is established by some critical note Fi 2 and 3 illustrate Steps n the manuor vibration as played back or set up by a phonof cture of he bulb. The leg 5 has one end theregraph record. Vibrations also occur at, harof inserted lengthwise into the peripheral edge monics of the resonance frequency; Such-vibraas of the bead 4 at a point out of line with the tions of the mount of the lamp, once set up, tend l Wires 3 as shown in Fig. 1. This le is then to prolong themselves even after the n te whi h bent downwardly to a position such that its lower initiated the vibration has been completed. The end- 6 is in a position to be p e ed into the expedient of increasing the size of the support fused glass formed at the seal between the bulb wires or of merely providing one or more addi- 40 neck I and the top tube 5. This position is tional support wires proved unsatisfactory. indicated roughly in Fig. 3. With the parts as- One object of the invention isa novel and vimsembled as shown in Fig. 3, the end of the neck I proved method of manufacture of a miniature andthe adjacent endof the top tube 5 are fused lamp with multiple mount supporti wires whereby and pressed together in sealing relation, the end the.objectionablevibrationsabove described are 40' 6 of the leg 0 being simultaneously embedded substantially eliminated and the operation-of in the fused mass at this juncture, as for example illustrated-in Figs. 4' and 5. After the top the lamp is improved.

Further objects of the invention will hereintube is sealed off at 5, a conventional base II is after appear. attached. In the particular embodiment of the For a better understanding of the invention so invention exhibited, the head 4 is slightly wider reference may be hadto the accompanying draw-- in the plane of the wire I, 3' than it is in the in: forming a part of this application, wherein plane transverse to the plane of the wires and Figs. 1 to 4 illustrate steps in the manufacture the anchor wire I is inserted into the edge of alamp bulb in accordance with the invention; of the bead at a point which is substantially and M equi-distant from the points where the support Fig. 5 is a view at right angles to Fig. ,4 showwires 3, 3 pass through the bead or which is ing the completed lamp. roughly removed therefrom on an arc join- Referring to Figs. 4 and 5 of the drawing, a ing all three points. miniature lamp embodying the invention is 11- This construction of miniature incandescent lustrated. This lamp embodies a bulb I, the 00 lamp eliminates and prevents any period of vibration, and particularly harmful vibrations which are transmitted to the head 4 and filament 2, with the result that lamps of this character not only tend to endure for their normal life with a minimum of premature failures, but also are eminently satisfactory for use in apparatus such as recording phonographs in which vibration would have deleterious effect upon the operation of the apparatus.

I claim:

1. The method of manufacturing a miniature incandescent lamp having a top tube fastened to the bulb neck thereof which comprises the steps of fusing a pair of leads to a refractory bead support and spacer, sealing an anchor support wire endwise to said bead at a point out of line with the points where the leads are fused, fusing a top tube endwise to the neck of the bulb, and during the last named fusing operation embedding said lead wires and said anchor wire into the mass of fused glass formed at the juncture between the neck and the top tube.

2. The method of manufacturing a miniature incandescent lamp comprising the steps of fusing and fastening a pair of leads to a supporting and spacing refractory bead, sealing an anchor wire endwise to said bead at a point ninety degrees removed from the points where the lead wires pass through the bead, formin the ends of the lead wires and the anchor wire into diverging relation so as to' extend into the vicinity of the-end of the bulb neck, fusing a top tube endwise to the bulb neck and simultaneously embedding the lead wires and the anchor wire into the mass of fused glass formed at the juncture between the neck and the top tube.

3. The method of manufacturing a miniature incandescent lamp having a top tube fastened to the bulb neck thereof which comprises the steps of fusing a pair of leads to a refractory bead support and spacer, sealing an anchor support wire endwise to said bead at a point out of line with the points where the leads are fused and on the peripheral edge of the bead; fusing a top tube'endwise to the neck of the bulb, and during the \last named fusing operation embedding said lead wires and said anchor wire into-the mass of fused glass formed at the juncture between the neck and the top tube.

REGINALD K. BRAUNSDORFF. 

